Platen rotating mechanism for stenographic typewriters



March 14, 1950 H. M. voN DUYKE PLATEN ROTATING MECHANISM FORsTENoGRAPHIc Twp-:WRITERS 2 Sheets-Sheet 1 Filed June 5, 1947 INVENTOR.,Er/figaro WLVozarZu'yZz,

March '14, 1950 H. M. voN DUYKE PLATEN ROTATING MECHANISM FORsTENoGRAPHIc TYPEWRITERS 2 ShsetS-Sheet 2 Filed June 3, 1947 PatentedMar. 14, 1950 UNITED PLATEN ROTATING MEUHANISM FOR STENOGRAPHICTYPEWRITERS Harrison M. Von Duyke, Wilmington, Del.

Application June 3, 1947, Serial No. 752,215

(Cl. IS7- 9) '7 Claims.

This invention relates to typewriter platen mechanism, and it relatesmore particularly to mechanism for rotating the platen of a stenographictypewriter, with a step by step movement, so constructed and arrangedthat each rotative movement of the platen follows the actuation of oneor more of the key levers.

The principal object of the present invention is to provide improvedmechanism for operating the platen of a stenographic typewriter whichwill be simple and efficient in 'its operation.

A further lobject of the invention is to provide mechanism, of thecharacter aforesaid, which will be positive in its action, yetpractically noiseless.

A further object of the invention is to provide mechanism, of thecharacter aforesaid, which will require a minimum of effort, on the partof the operator, in its actuation.

A further object of the invention lis to provide mechanism, of thecharacter aforesaid, the various parts of which are readily accessible,and which is so constructed and arranged that it may be quickly andeasily taken apart and reassembled for the purpose of repair andreplacement of worn or damaged parts.

The nature and characteristic features of the present invention will bemore readily under stood from the following description, taken inconnection with the accompanying drawings forming part hereof, in which:

Figure 1 is a top or plan View of a stenographic typewriter, certainparts being removed and omitted for the purpose of illustrating platenoperating mechanism embodying the main features of the presentinvention;

Fig. 2 is a side elevation thereof enlarged;

Fig. 3 is a transverse vertical sectional view,

It should, of course, be understood that the y description and drawingsherein are illustrative merely, and that various modifications andchanges lmay be made in the structure disclosed without departing fromthe spirit -of the `invention.

Referring to the drawings, in the particular embodiment of the inventiontherein shown, l0 and Il are side plates comprising portions of theframe work of the machine. Extending across between the frames l0 and lI, and projecting beyond the outer faces thereof, on each side, is apivot pin l2 upon which the key levers i3 of the typewriter are pivoted.This pivot pin I2 also serves as a means for mounting pivoted bracketarms lil and i5, the forward ends of which are secured to and serve -tosupport a channel bar it. The bar It extends across the machine belowthe key levers and supports a strip of felt il' against which the bottomedges of the lkey levers bear. For the purpose of holding the feltmember Il against the lower edges of the key levers i3 there areprovided, on each side of the machine, lcoil springs I 8. The lower endof each of said coil springs i' is secured to lthe respective bracketarms Ill or l5, and the upper end of each of said coil springs issecured to a pin member i9 which is mounted in one of the side plates ofthe machine.

The bracket arm Id on one side of the machine is provided with aprojecting arm 2B having a tooth 2l at the outer end thereof. The tooth2l engages a recess `22 in a member 23 which is also pivotally mounted,by means of a pin 24, von the side plate lll of the machine.- The member23 is provided with a rearwardly extending portion in which a series ofgear teeth 25 are provided.

The platen 2t is mounted on a suitable shaft 21 which is journaled inbearing bushings 23 which are seated in the side frames lll and Il. Thebearing bushings are held in place on the platen shaft 21 by means ofsnap washers 29 normally positioned in grooves in the projecting endportions of the platen shaft 2l.

A rotatable member is journale-d on the platen shaft 2l and is normallyheld in place thereon by means of a snap washer 3! which vis seated in asuitable groove in the shaft 2'?. The rotatable member 3@ has a portionprovided with a plurality of gear teeth 32 which are engaged by the gearteeth 25 of the member 23, the arrangement being such that when .themember 2t lis actuated, themotion thereof will be transmitted to themember all, which as before stated, is journaled on the platen shaft 2l.

The member Sli is also provided with a radially extending pin 33 to thefree end of which one end of a coil spring 34 is connected. The otherend of the coil spring 34 is connected to a pin 35 secured in the sidewall il) of the frame. The tension of the spring 34 normally tends toreatodos? turn the member 30 to its initial position after the key leveror levers is released.

The rotatable member 3i] is also provided with a downwardly extendingpin member 36, which is so positioned that the lower end thereof will,when the member 30 is rotated too far, encounter the pin 35 to which thecoil spring 34 is connected. This arrangement is provided to limit themovement of the rotatable member 30, and is particularly desirable forsuch purpose when the platen is rapidly rotated or spun by the operatori in the removal of a completed transcript from the l machine.

The rotatable member 3B is also provided with of wedge shaped pockets,in each of which a ball 4I is mounted.

The foregoing arrangement is such that when the member 30 is rotated inone direction, the

balls 4I will abut against the substantially radial y faces 40 of themember 30, and will then permit the member to rotate freely, but uponthe reversal of the direction of rotation, after a depressed lever orlevers have been released, at

least one of the balls 4I will be wedged in one of the pockets and willconstrain the ratchet like member 38, and thereby the platen shaft 21,to be rotated. Y -K Y A cover member 42 is provided having a collarportion 43 which overlaps the collar portion 31 of the member 30. Thiscover member 42 is maintained in position to protect and position theindividual parts of the friction ratchet mechanism above described bymeans of a snap washer 44 which is mounted in a groove on the end of theplaten shaft 21.

The operation of the mechanism above dei scribed will now be readilyunderstood. When- 1 ever one or more of the key levers I3 is depressed,

the movement thereof will be communicated to the pivoted bracket arms I4and I5 through the felt strip I1 and channel bar I6 which are supportedat the front ends of said bracket arms I4 and I5. Said movement of thebracket arm I4 wil1 then be communicated by the extension 20 thereof tothe tooth 2| at the end thereof and thence to the pivoted member 23.

The movement of the pivoted member 23 will in turn be transmitted by thegear teeth '25 thereof to the rotatable member 30 by means of the gearteeth 32 carried thereby. The member 30 will thus be caused to rotate onthe platen shaft 21, such movement being permitted by reason of theballs 4| being carried to the radial faces of the ratchet like member38. Said balls being thus brought to the larger ends of the respectivepockets in which said balls are positioned, there will be no movement ofthe platen when the key lever is depressed.

However, upon the release of the key lever or levers, as the case maybe, one or more of the balls 4 I will be wedged in the tapered pocketsprovided between the working surfaces 39 of the y ratchet like member 38and the collar portion 31 of the member 30. The platen shaft 21 willthen be rotated a short distance through the 4 tension of the spring 34,as well as the springs I8 which tend to return the bracket arms I4 andI5 to their initial positions.

The coil spring 34 not only assists the bracket arm springs I8, but ithas been found in practice that the provision of an additional spring atthis particular location, acting directly on the rotatable member 30,results in a more balanced operation of the parts, and enhances thefreedom of operation of the machine.

I claim:

l. In a typewriter of the character described having a plurality of keylevers which may be operated separately, or of which two or more may beoperated simultaneously, and having a platen ladapted tobe advanced uponthe release of depressed key levers, means for actuating said platencomprising a bar extending across the machine beneath the key levers andadapted to be depressed when one or more of said key levers isdepressed, pivoted bracket arms for supporting said bar, one of saidbracket arms having an extending portion, a pivoted member having arecess engaged by a part of the extending portion of said one bracketarm, said pivoted member` having a plurality of gear yteeth on anextending portion thereof, ya rotatable member mounted on the platenshaft having a series of gear teeth engaged by the gear teeth of theaforesaid pivoted member, a ratchet like member mounted on a projectingend portion of the platen shaft; said ratchet like member havingsurfaces shaped to provide, in conjunction with a portion of therotatable member, a pluralty of `wedge shaped pockets, balls insaidpockets adapted when the member on the platen shaft is rotated inone direction to be positioned in the wideportions of said pockets andvwhen the memberfon the platen shaft is rotated in the other direction towedge in said pockets to frictionally couple said rotatable member andsaid ratchet like member, and springs for returning the bracket arms totheir normal raised positions and thereby actuating the platen.

2. In a typewriter of the character described having a plurality of keylevers which may be operated separately, or of which two or more may beoperated simultaneously, and having a platen adapted to be advanced uponthe release of depressed key levers, means for actuating said platencomprising a bar extendingl across the machine beneath the key leversand adapted to be depressed when one or more of said key levers isdepressed, pivoted bracket arms for supporting said bar, one of saidbracket arms having an extending portion'provided with a tooth, apivoted member having a recess engaged by said tooth of theextendingportion of said one bracket arm, said pivoted member having aplurality of gear teeth on lan extending portion thereof, a rotatablemember mounted on the platen shaft having a series of gear teeth engagedby the gear teeth of the aforesaid pivoted member, a ratchet like membermounted on a projecting end portion of the platen shaft, said ratchetlike member having surfaces shaped to provide, in conjunction with aportion of the rotatable member, a plurality of wedge shaped pockets,balls in said pockets adapted when the member on the platen shaft isrotated in one direction to be positioned in the wide portions of saidpockets and when the member on the platen shaft is rotated in the otherdirection to wedge in said pockets to frictionally couple said rotatablemember and said ratchet like member, and springs for returning .5 thebracket armste their normal raised positions and for simultaneouslyactuating the platen.

'3. In a typewriter of the character described having a plurality of keylevers which may be operated separately, or of .which two or more may beoperated simultaneously, and having a platen adapted to be advanced upontherrelease of depressed key levers, means for actuating said platencomprisingwa bar extending across the machine beneath the keylevers andadapted to be depressed when one or more of said key levers isdepressed, pivoted bracket arms for supporting said bar, one of saidbracket arms having an extending portion provided with a tooth, apivoted member having a recess engaged by said tooth of the extendingportion of said one bracket arm, said pivoted member having a pluralityof gear teeth on an extending portion thereof, a rotatable membermounted on the platen shaft having a series of gear teeth engaged by thegear teeth of the aforesaid member, a ratchet like member mounted on aprojecting end portion of the platen shaft, said ratchet like memberhaving surfaces shaped to provide, in conjunction with a portion of therotatable member, a plurality of wedge shaped pockets, balls in saidpockets adapted when the member on the platen shaft is rotated in onedirection to be positioned in the wide portions of said pockets and whenthe member on the platen shaft is rotated in the other direction towedge in said pockets to frictionally couple said rotatable member andsaid ratchet like member, coil springs for returning the bracket arms totheir normal positions, and a separate spring connected directly to therotatable member on the platen shaft tending to return the same to itsinitial position.

4. In a typewriter of the character described having a plurality of keylevers which may be operated separately, or of which two or more may beoperated simultaneously, and having a platen adapted to be advanced uponthe release of depressed key levers, means for actuating said platencomprising a bar extending across the machine beneath the key levers andadapted to be actuated When one or more of said key levers is depressed,pivoted bracket arms for supportingT said bar, one of said bracket armshaving an extending portion provided with a tooth, a pivoted memberhaving a recess engaged by said tooth of the extending portion of saidone bracket arm, said pivoted member having a plurality of gear teeth onan extending portion thereof, a rotatable member mounted on the platenshaft having a series of gear teeth engaged by the gear teeth of theaforesaid pivoted member, a ratchet like member mounted on a projectingend portion of the platen shaft, said ratchet like member havingsurfaces shaped to provide, in conjunction with a portion of therotatable member, a plurality of wedge shaped pockets, balls in saidpockets adapted when the member on the platen shaft it rotated in onedirection to be positioned in the wide portions of said pockets and whenthe member on the platen shaft is rotated in the other direction towedge in said pockets to frictionally couple said rotatable member andsaid ratchet like member, coil springs for returning the bracket arms totheir normal raised positions, a separate spring connected directly tothe rotatable member on the platen shaft tending to return the same toits initial position, -and means for limiting the movement of saidrotatable member.

5. In a typewriter of the character described having a plurality ofkey'iev'ers 'maybe operated separately, or of whichv two or more'may beoperated simultaneously, and having a platen adapted te be advanced uponthe 'release of depressed key levers, means for actuating said platencomprising 'a bar extending across the machine beneath the key leversand 'adapted te be depressed when one or more of said key 'levers isdepressed, pivoted bracket arms for supporting said bar, one of saidbracket 'arms' having an extending portion provided with' a tooth,` apivoted member having a recess k engaged said tooth of the extendingportion of said one bracket arm, said pivoted member having a pluralityof gear teeth on an extending portion thereof, a rotatable membermounted on the platen shaft having a series of gear teeth engaged by thegear teeth of the aforesaid pivoted member, a frictional ratchet deviceadapted to permit the member on the platen shaft to be freely rotated inone direction and when the member on the platen shaft is rotated in theother direction to couple said rotatable member to the platen shaft andsprings for returning the bracket arms to their normal raised positions.

6. In a typewriter of the character described having a plurality of keylevers which may be operated separately, or of which two or more may beoperated simultaneously, and having a platen adapted to be advanced uponthe release of depressed key levers, means for actuating said platencomprising a bar extending across the machine beneath the key levers andadapted to be actuated when one or more of said key levers is depressed,pivoted bracket arms for supporting said bar, one of said bracket armshaving an extending portion provided with a tooth, a pivoted memberhaving a recess engaged by said tooth of the extending portion of saidone bracket arm, said pivoted member having a plurality of gear teeth onan extending portion thereof, a rotatable member mounted on the platenshaft having a series of gear teeth engaged by the gear teeth of theaforesaid pivoted member, a frictional ratchet device adapted to permitthe member on the platen shaft to be freely rotated in one direction andwhen the member on the platen is rotated in the other direction tocouple said rotatable member to the platen shaft, springs for returningthe bracket arms to their normal raised positions, and a separate springconnected directly to the rotatable member on the platen shaft tendingto return the same to its initial position and thereby actuate theplaten.

7. In a typewriter of the character described having a plurality of keylevers which may be operated separately, or of which two or more may beoperated simultaneously, and having a platen adapted to be advanced uponthe release of depressed key levers, means for actuating said platencomprising a bar extending across the machine beneath the key levers andadapted to be actuated when one or more of said key levers is depressed,pivoted bracket arms for supporting said bar, one of said bracket armshaving an extending portion provided with a tooth, a pivoted memberhaving a recess engaged by said tooth of the extending portion of saidone bracket arm, said pivoted member having a plurality of gear teeth onan extending portion thereof, a rotatable member mounted on the platenshaft having a series of gear teeth engaged by the gear teeth of theaforesaid pivoted member, a fric- 7 tional ratchet device adapted topermit the member on the platen shaft to be freely rotated in onedirection and when the member on the platen shaft is rotated in theother direction to couple said rotatable member to the platen shaft,coil springs for returning the bracket arms to their normal raisedpositions, a separate spring connected directly to the rotatable memberon the platen shaft tending to return the same to its initial positionand thereby actuate the platen, and means for limiting the movement ofsaid rotatable member.

HARRISON M. VON DUYKE.

REFERENCES CITED The following references are of record in `the iile ofthis patent:

UNITED STATES PATENTS Number l Name Date 1,318,323 Ireland Oct. 7, 19191,933,833 Westlund et al. Nov. 7, 1933 FOREIGN PATENTS l Number CountryDate 557,904 France of 1923

